Feeding of machines

ABSTRACT

The invention comprises a method of, and apparatus for, feeding sheets to a machine. A sheet has one edge secured temporarily to a cylinder after such edge has been placed under tension and such edge is carried down by the cylinder and released onto an endless conveyor which feeds the sheet to the machine. The sheet edge is preferably secured by suction through openings in the cylinder wall and tensioned by at least one gripping means adapted to have linear movement parallel with the cylinder axis.

United States Patent Hall 1 June 6, 1972 FEEDING 0F MACHINES 1,912,724 6 1933 Remington ..38/143 ux 3,198,315 8/1965 Long [72] Invent 9" England 3,414,997 12/1968 Henry ..38/143 [73] Assignee: Baker Perkins Jaxons Limited, Glasgow,

Scotland Primary Examiner.loseph Wegbreit Att Ste ,D ,Mill &M h Filed: y 1970 orney vens av1s er 0s er [21 Appl. No.2 40,602 ABSTRACT The invention comprises a method of, and apparatus for, feedljz] Cl 338/143, 271/45 ing sheets to a machinev A sheet has one edge secured tem- 51 1m. 01. ..D06f 67/04 Pman'ly 3 cylinde after such edge has been Placed under [58] Field ofSearch ..38 143 271/45 46 and Such edge is carried by the cylinder and released onto an endless conveyor which feeds the sheet to the [56] References Cited machine. The sheet edge is preferably secured by suction through openings in the cylinder wall and tensioned by at least ED STATES PATENTS one gripping means adapted to have linear movement parallel with the cylinder axis. 3,425,144 2/1969 Petterson ..38/143 2,654,969 10/ l 953 Woodward ..38/143 7 Claims, 5 Drawing Figures 74 7 i L jZ: '2 ;& W T

i 75 7 I 1 I 1 "5 A L 1 5 h. v

E I" 1 2d 2'4 l l 9 f PATENTEDJun 6l9 72 3.667.143

' sum 20F a This invention relates to the feeding of sheet material, sheets or other flat articles (hereinafter for convenience termed sheets) to machines.

The invention is particularly concerned with the feeding of washed sheets to a calender for ironing. A calender in a laundry usually comprises a hollow bed with superposed hollow rollers lying in troughs in the bed. The bed and rollers are heated, usually by steam, and an endless multi-tape feed conveyor is mounted in front of the bed.

The usual feeding method requires two persons to grasp the leading corners of a sheet, tension the leading edge to remove wrinkles and simultaneously to place the edge on the feed conveyor. Thus a sheet will enter the calender parallel with the first roller axis, free from wrinkles and tension. Unless the sheet is presented in this manner the ironing and subsequent folding will be impaired. In order that the two feeders may keep the machine working to capacity a prior operation is performed, usually by two further operators.

According to the present invention there is provided a method of feeding sheets to a machine consisting in causing the leading edge of the sheet to be gripped and tensioned linearly of such edge for it to lie parallel with the axis of a rotary feed cylinder, causing such leading edge to be held on to the cylinder periphery, rotating the cylinder for it to lay said edge down on to a moving endless feed conveyor below the cylinder, arranging the following part of the cylinder periphery to press the sheet on to the conveyor to hold it against relative movement, and then allowing the conveyor to feed the sheet to the machine.

The method preferably includes holding the sheet edge on to the periphery by suction.

The method desirably also includes rotating the cylinder at required intervals at a surface speed greater than that of the conveyor during part of the cylinder rotation, and then at the same speed as the conveyor. The sheet edge may be tensioned by causing gripping means to traverse across in front of the cylinder. The cylinder can be mounted to be capable of rising and falling in relation to the conveyor.

The invention will now be more particularly described with reference to the accompanying drawings, in which:

FIG. 1 is a front elevation of the improved sheet feeding device;

FIG. 2 is a side elevation of FIG. 1;

FIGS. 3, 4 and 5 are diagrammatic views showing the movement of a sheet about the feed cylinder to the sheet conveyor.

In a particular embodiment of this invention a sheet feeding device comprises a cylinder 1 which is supported at its ends, say, by guide rollers 2 engaging its periphery (or by a shaft or stub shafts) so that the cylinder can be driven by an electric motor 3 and belt 4, or other means. This cylinder is carried by end frames 5 and arms 6 to be movable about a pivot 7 in relation to a multi-tape or other feed conveyor 8 in advance of a calendar 9. A pneumatic piston and cylinder unit 10 is pivoted to a mounting bracket 11 and attached to each arm 6 for raising and lowering the cylinder 1. The conveyor 8 is arranged so that the upper run of the conveyor is inclined upwardly towards the calender, then travels in a horizontal plane and then inclines sharply downwardly for sheets to be fed into the nip of the first calender roller 12 and calender bed 13. The cylinder for part of its periphery, say about half, is provided with pressure pads 14 of resilient material which conveniently may be of cellular rubber or plastics material. In the other, uncovered, part of the cylinder periphery, a series of slots 15 (or holes) are provided in one (or more) row lengthwise of the cylinder to form suction openings when a vacuum is created in the cylinder through a suction fan connection 16. Adjacent the cylinder there is provided gripping means 17 which is in the form of a double jawed clip arranged to be moved along the length of the cylinder in advance thereof. These clip jaws comprise a cup and co-acting inflatable diaphragm to trap a sheet corner therebetween when a valve is opened in an air supply line. The clip is mounted on a carriage 18 which runs on a track 19 and is operated by a long rod 20 which swings horizontally about a pivot. A pneumatic piston and cylinder unit (or other means) can operate the rod 20 which can slide in a pivotal mounting bracket 21.

In operation the leading edge 22 of a sheet 23 can be lifted and one corner inserted into the clip 17 which can then be traversed along the cylinder whilst the operator is holding the nearest comer of the sheet. Thus the leading edge 22 will be tensioned to straighten it and on reaching the other end of the cylinder the tension applied by the operator at one end may be used to cause the clip to automatically release the sheet, or such clip can be positively caused to release the sheet, as soon as a vacuum has been created in the cylinder which will cause the leading edge of the sheet to be sucked against the periphery of the cylinder. Immediately the sheet is so held the cylinder is positively rotated at a surface speed greater than that of the conveyor 8 to carry the sheet edge downwards and briefly the latter edge will be turned back (FIG. 4) on itself. Continued rotation will (because of the difference in speed between the conveyor and cylinder) momentarily tension the sheet in the direction of travel. This tension will be sufficient to peel the sheet from the suction openings 15. As the sheet leading edge clears the suction openings the aforesaid pressure pads 14 will take charge of the sheet to press it firmly on to the conveyor. Continued rotation of the cylinder is at the same surface speed as the conveyor and the pressure pads will have rolling contact with the sheet for a length of time sufficient to ensure that the conveyor will continue to feed the sheet forwardly to the calender 9, and thereafter to return the cylinder to the starting position. It will be understood that the cylinder may be positively driven initially and then be rotated by the frictional grip of the pressure pads on the conveyor, through the medium of the sheet, so that cylinder and conveyor move at the same surface speed. This arrangement dispenses with the need for a variable speed drive and need simply require a clutch. Alternatively, the cylinder may have a variable speed drive so that it initially rotates at an accelerated speed in relation to the conveyor and then changes to the same surface speed.

The sheet may be given some tension transversely to obviate creasing and this may be accomplished by a crossed endless belt 24 on end pulleys 25, or a tensioning curved bar or other means. The sheet, after the leading edge is firmly held on the conveyor, can have its body deposited to hang down into a trough 26 by opening a hinged flap 27 operated by an air piston-cylinder unit 28.

Some other means for operating the clip 17 or other gripping means may be employed. If required the tail end of the sheet may be held by a known form of device or means other than that disclosed.

Instead of the nearest comer of a sheet being held by the feed operator whilst the other comer is being traversed by the gripping means 17, further gripping means may be used to hold said nearest comer. If desired a pair of sheet gripping means may be traversed in opposite directions to tension a sheet on the cylinder.

I claim:

1. Apparatus for feeding an ironing machine with spreadout sheet material comprising a rotatably mounted feed member, a continuous feed conveyor below said feed member, a spreading device for spreading the leading edge of the sheet material over said feed member so that said leading edge lies substantially parallel to the axis of rotation of said feed member, retaining means for causing said spread leading edge to be held on an external surface of said feed member, an arcuate pressure pad on an external surface of said feed member adapted to hold sheet material between said pressure pad and said conveyor, means for driving said conveyor, means for rotating said feed member in a direction such that said retaining means precedes said pressure pad and at a first speed such that the linear speed of the surface of said pressure pad is at first greater than the linear speed of said conveyor and for thereafter rotating said feed member at a second speed such that the linear speed of the surface of said pressure pad is equal to that of said conveyor.

2. The apparatus according to claim 1, wherein said retaining means comprises at least one elongate suction opening, disposed along the direction of the axis of rotation of said feed member, through an external wall of said feed member, and means for providing a vacuum within said opening for retaining the spread leading edge on the surface of said feed member.

3. The apparatus according to claim 1, wherein said elongate opening comprises a plurality of openings.

4. The apparatus according to claim 1, wherein said spreading device comprises a guide track extending lengthwise of the feed member, a carriage movable on said guide track, a sheet gripping device mounted on said carriage, and means for causing said carriage to travel along said guide track.

5. The apparatus according to claim 4, additionally comprising air operated means for operating said sheet gripping device.

6. The apparatus according to claim 1, additionally comprising pivotal mounting means supporting said feed member for movement relative to said conveyor.

7. The apparatus according to claim 1, additionally comprising means for tensioning said sheet material as it approaches said feed conveyor. 

1. Apparatus for feeding an ironing machine with spread-out sheet material comprising a rotatably mounted feed member, a continuous feed conveyor below said feed member, a spreading device for spreading the leading edge of the sheet material over said feed member so that said leading edge lies substantially parallel to the axis of rotation of said feed member, retaining means for causing said spread leading edge to be held on an external surface of said feed member, an arcuate pressure pad on an external surface of said feed member adapted to hold sheet material between said pressure pad and said conveyor, means for driving said conveyor, means for rotating said feed member in a direction such that said retaining means precedes said pressure pad and at a first speed such that the linear speed of the surface of said pressure pad is at first greater than the linear speed of said conveyor and for thereafter rotating said feed member at a second speed such that the linear speed of the surface of said pressure pad is equal to that of said conveyor.
 2. The apparatus according to claim 1, wherein said retaining means comprises at least one elongate suction opening, disposed along the direction of the axis of rotation of said feed member, through an external wall of said feed member, and means for providing a vacuum within said opening for retaining the spread leading edge on the surface of said feed member.
 3. The apparatus according to claim 1, wherein said elongate opening comprises a plurality of openings.
 4. The apparatus according to claim 1, wherein said spreading device comprises a guide track extending lengthwise of the feed member, a carriage movable on said guide track, a sheet gripping device mounted on said carriage, and means for causing said carriage to travel along said guide track.
 5. The apparatus according to claim 4, additionally comprising air operated means for operating said sheet gripping device.
 6. The apparatus according to claim 1, additionally comprising pivotal mounting means supporting said feed member for movement relative to said conveyor.
 7. The apparatus according to claim 1, additionally comprising means for tensioning said sheet material as it approaches said feed conveyor. 